Manual Flash Photography
Flash Photography Tip 4
We discussed TTL flash photography in previous articles and in this article I am going to show you the advantages of Manual flash photography.
There are two distinct ways in which flash exposure is controlled – Manual flash or TTL flash. Just Like Manual Exposure, Manual Flash requires more attention to camera and flash settings. When you master these techniques, you will enjoy flash photography even more and be able to create amazing pictures. With manual flash, you adjust your settings to achieve a correct flash exposure. You can use a light-meter, or even the histogram, to get correct flash exposure.
As I mentioned before, correct flash exposure requires four things to be controlled and balanced:
– Aperture
– ISO
– Distance (from the flash to subject)
– Power (the flash’s actual blitz of light, taking into consideration any diffusion)
You know about the roles of Aperture and ISO and for this article I am going to introduce the influences of Distance and Power.
Firstly, flash could simply be a constant amount of light that is emitted from the flashgun. In the case of manual flash, there is NO control by the flashgun or camera, either with the intensity or duration of the pulse of light from the flash unit.
This is manual flash. Photographers can control the output of their flashguns by adjusting the settings in fractions of the maximum possible output, ( 1/2 power, 1/4 power, 1/16 power, etc.). It should be obvious that the absolute value of ¼ power will vary from flashgun to flashgun, as each model and make of flashgun has a different maximum power. The power of a flashgun is measured by GUIDE NUMBER; the higher the guide number the more output of power.
To recap, with manual flash we have four controls for the flash exposure:
– the actual output level from the flashgun, (the ratio of full or partial power),
– distance from our light source to the subject
– aperture
– ISO.
Any of these four variables can be used to control the amount of light falling on your subject.
TTL vs. Manual flash photography
The only way to control TTL flash metering is with flash exposure compensation. While you could control manual flash exposure with any of the four variables mentioned above, with TTL flash you have one option and this is with your flash exposure compensation.
With manual flash, since the flash is a specific level, our subject’s reflectivity or our choice of composition (how we frame our subject) has absolutely no impact on our metering. This is a hugely important aspect of manual flash. Once we have our lights set up at a specific distance, and determined our aperture and ISO…the subject’s reflectivity (how much lighter tones or darker tones there are) have NO effect on our flash exposure.
However, with TTL flash the subject’s reflectivity / tonality and our choice of composition WILL affect our flash exposure. And hence, we often need to control our flash exposure with the flash exposure compensation.
The concepts explained in this section are so essential to our further understanding of flash photography that I strongly suggest re-reading this section until it makes sense. Also check our Upcoming Classes page to find a workshop in Manual Exposure or Manual Flash Photography. Gaining a solid understanding, both in theory and in practice, about flash photography will open up a whole new creative world to you. Feel free to contact us if you have any questions about your flash and/or camera settings.
That is all for now. Stay tuned for more articles about creative uses of TTL and Manual Flash Photography, such as Slow Shutter synch and off-camera flash photography.
Ted and the Omnilargess Team
Our TTL Flash Photography workshop is scheduled for July 6th 2016. This is a 2 part workshop with lots of practical settings.